Not even wrong: the spurious measurement of biodiversity's effects on ecosystem functioning

Area of Science:

• Ecology
• Ecosystem Science

Background:

• Biodiversity's influence on ecosystem functioning is a key ecological question.
• Previous research focused on "selection" and "complementarity" effects to explain this relationship.
• These explanations relied on statistical partitioning methods.

Purpose of the Study:

• To critically re-evaluate the statistical methods used to partition biodiversity effects.
• To identify flaws in the commonly used "selection" and "complementarity" effect calculations.
• To propose an improved approach for estimating biodiversity's impact on ecosystem functioning.

Main Methods:

• Analysis of existing statistical partitioning schemes for biodiversity effects.
• Evaluation of null expectations and their influence on effect size estimations.
• Consideration of nonlinear relationships between species abundance and ecosystem functioning.

Main Results:

• Current methods for calculating biodiversity effects are fundamentally flawed.
• Naïve null expectations lead to overestimation of biodiversity's net effect.
• Failure to account for nonlinear abundance-functioning relationships further biases results.

Conclusions:

• The widely accepted "selection" and "complementarity" effects likely overestimate biodiversity's positive impact.
• Existing statistical frameworks are inadequate for partitioning biodiversity effects, especially under nonlinearity.
• An alternative approach is proposed for more accurate estimation of biodiversity effects on ecosystem functioning.